Polyurethane coating material compositions and use thereof for producing multicoat paint systems

ABSTRACT

Disclosed herein is a coating material compositions containing (A) a polyhydroxyl group-containing component, (B) a component (B) having on average at least one isocyanate group and having on average at least one of: at least one hydrolyzable silane group of the formula (I): —NR—(X—SiR″x(OR′)3-x), and at least one hydrolyzable silane group of the formula (II): —N(X—SiR″x(OR′)3-x)n(X′—SiR″y(OR′)3-y)m, (D) a phosphorus and nitrogencontaining catalyst, and a catalyst (Z), wherein: the catalyst (Z) is selected from zinc and bismuth carboxylates, of aluminum, zirconium, titanium and/or boron chelates and/or of inorganic, tin-containing catalysts, and mixtures thereof; and the coating material composition comprises at least one reaction accelerator (R) which is selected from the group of inorganic acids and/or of organic acids and/or of partial esters of the inorganic acids and/or of partial esters of the organic acids. Processes for producing multicoat paint systems, and coatings obtained from the coating material compositions are also disclosed.

This application is a U.S. National Stage Application under 35 U.S.C. §371 of International Application No. PCT/EP2016/062368 filed on Jun. 01,2016, and claims benefit to European Patent Application No. EO15172102.4 filed on Jun. 15, 2015, which are all hereby incorporated intheir entirety by reference.

The present invention relates to coating material compositionscomprising at least one polyhydroxyl group-containing component (A), atleast one component (B) having on average at least one isocyanate groupand having an average of at least one hydrolyzable silane group, atleast one phosphorus- and nitrogen-containing catalyst (D) for thecrosslinking of silane groups, and at least one catalyst (Z) for thereaction of the hydroxyl groups with the isocyanate groups. It alsorelates to a process for producing multicoat paint systems using thesecoating material compositions, and also to the multicoat systemsproducible by means of this process.

PRIOR ART

Coating material compositions based on polyurethanes and also their useas the topmost clearcoat of multicoat paint systems have been known fora long time. Also known is that through the use of polyisocyanatecrosslinkers which additionally have hydrolyzable silane groups, it ispossible to achieve substantial improvements in the scratch resistanceof the resulting multicoat paint systems. Particularly if the coatingsare cured at relatively low temperatures of not more than 90° C., as arecustomarily for automotive refinishing and also for the coating of partsfor installation in or on automobiles and of commercial vehicles, thesimultaneous crosslinking via the silane groups and the OH/NCO reactionis a very important aspect.

For example, WO 09/077180 describes coating material compositions whichcomprise polyisocyanate crosslinkers having additional hydrolyzablesilane groups and, as catalysts, in particular1,4-diazabicyclo[2.2.2]octane (DABCO)-blocked bis (2-ethylhexyl)phosphate and which are used in particular for coatings which are curedat low temperatures, more particularly of 30 to 90° C.

WO 09/077182 describes coating material compositions which comprisepolyisocyanate crosslinkers having additional hydrolyzable silane groupsand, as catalyst, triethylamine-blocked bis(2-ethylhexyl) phosphate, andalso, as further catalyst, amines, more particularly bicyclic amines,such as, for example, 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) or1,5-diazabicyclo[4.3.0]non-5-ene (DBN).

Still requiring of improvement in both coating materials, however, isthe curing of the coating materials at the low baking temperatures of100° C. at most.

Furthermore, WO 2014/016026 describes coating material compositionswhich comprise polyisocyanate crosslinkers having additionalhydrolyzable silane groups and, as catalyst,1,4-diazabicyclo[2.2.2]octane (DABCO)-blocked bis(2-ethylhexyl)phosphate, and also, as further catalyst, a monomeric aromatic,optionally substituted, carboxylic acid (S) whose carboxyl group is inconjugation with a π-electron system, more particularly benzoic acid.Deserving of improvement in the case of these coating materials is thechemical resistance, especially the resistance toward sodium hydroxidesolution, and also the hardness of the coatings immediately aftercuring. A reduction in the onset temperature is desirable as well.

WO 2014/077180, finally, describes coating material compositions basedon silanized ioscyanate crosslinkers, these compositions comprising zincamidine complexes as catalyst and, as a further component, at least onearomatic monocarboxylic acid, more particularly benzoic acid. Adisadvantage with these coating materials, however, is the yellowingtendency of the catalyst used, especially at elevated temperatures of 60to 100° C.

Problem

The problem addressed by the present invention was therefore that ofeliminating the above-described disadvantages of the prior art. Theintention was therefore to provide coating material compositions of thetype stated at the introduction that immediately after curing attemperatures of not more than 100° C., more particularly of not morethan 90° C., exhibit good packing resistance and good assembly strengthon the part of the resultant coatings. The desire is therefore for avery low onset temperature, in other words a very low temperature atwhich crosslinking begins.

Furthermore, the coating material compositions, even on curing attemperatures of not more 100° C., more particularly of not more than 90°C., ought to ensure not only good hardnesses and scratch resistances onthe part of the resultant coating, but also, at the same time, goodchemical resistance of the resultant coating.

Additionally, the coating material compositions ought to lead tocoatings having extremely low thermal yellowing, especially in thecontext of the tests customarily in the OEM finishing sector, such asthe BMW test, for example, in other words on storage at 100° C. for 7days. Moreover, they ought also to fulfill the qualities customarilyrequired in the sector of the finishing of commercial vehicles and partsfor installation in or on automobiles.

Finally, the coating material compositions used in the process ought tobe able to be produced easily and with very good reducibility, and oughtnot to cause any environmental problems during coating-materialapplication.

Solution to the Problem

Found accordingly have been coating material compositions comprising

-   a) at least one polyhydroxyl group-containing component (A),-   b) at least one component (B) having on average at least one    isocyanate group and having on average    -   at least one hydrolyzable silane group of the formula (I)        —NR—(X—SiR″_(x)(OR′)_(3-x))  (I),    -   and/or    -   at least one hydrolyzable silane group of the formula (II)        —N(X—SiR″_(x)(OR′)_(3-x))_(n)(X′—SiR″_(y)(OR′)_(3-y))_(m)  (II),    -   where        -   R=hydrogen, alkyl, cycloalkyl, aryl, or aralkyl, it being            possible for the carbon chain to be interrupted by            nonadjacent oxygen, sulfur, or NRa groups, where Ra=alkyl,            cycloalkyl, aryl, or aralkyl,        -   R′=hydrogen, alkyl, or cycloalkyl, it being possible for the            carbon chain to be interrupted by nonadjacent oxygen,            sulfur, or NRb groups with Rb=alkyl, cycloalkyl, aryl, or            aralkyl, preferably R′=ethyl and/or methyl,        -   X, X′=linear and/or branched alkylene or cycloalkylene            radical having 1 to 20 carbon atoms, preferably X,            X′=alkylene radical having 1 to 4 carbon atoms,        -   R″=alkyl, cycloalkyl, aryl, or aralkyl, it being possible            for the carbon chain to be interrupted by nonadjacent            oxygen, sulfur, or NRc groups, with NRc=alkyl, cycloalkyl,            aryl, or aralkyl, preferably R″=alkyl radical, more            particularly having 1 to 6 C atoms,        -   n=0 to 2, m=0 to 2, m+n=2, and x, y=0 to 2,-   c) at least one phosphorus and nitrogen-containing catalyst (D) for    the crosslinking of silane groups, and-   d) at least one catalyst (Z) for the reaction of the hydroxyl groups    with the isocyanate groups,    wherein-   i. the catalyst (Z) is selected from the group of zinc and bismuth    carboxylates, of aluminum, zirconium, titanium and/or boron chelates    and/or of inorganic, tin-containing catalysts, and mixtures thereof,    and-   ii. the coating material composition comprises at least one reaction    accelerator (R) which is selected from the group of inorganic acids    and/or of organic acids and/or of partial esters of the inorganic    acids and/or of partial esters of the organic acids.

The present invention further provides processes for producing multicoatpaint systems using the coating material compositions, and also thecoatings obtainable by this process, and also the use thereof. Preferredembodiments are apparent from the description hereinafter and from thedependent claims.

It is surprising and was not foreseeable that the coatings produced withthe coating material compositions of the invention, immediately aftercuring at temperatures of not more than 100° C., more particularly ofnot more than 90° C., exhibit good packing resistance and good assemblystrength. The coating material compositions of the invention arenotably, furthermore, for a low onset temperature, in other words for alow temperature at which crosslinking begins.

Furthermore, even on curing at temperatures of not more than 100° C.,more particularly of not more than 90° C., the coating materialcompositions lead to coatings having good hardness and scratchresistance and also, at the same time, good chemical resistance.

Furthermore, the coating material compositions lead to coatings havingextremely low thermal yellowing, especially in the context of the testscustomarily in the sector of OEM finishing, such as the BMW test, forexample, in other words on storage at 100° C. for 7 days. They also,moreover, realize the properties customarily required within the sectorof the finishing of commercial vehicles and of parts for installation inor on automobiles.

Lastly, the coating material compositions can be produced easily andvery reproducibly, and do not give rise to any environmental problemsduring the coating-material application.

DESCRIPTION OF THE INVENTION

The Inventively Employed Coating Materials

For the purposes of the present invention, constant conditions wereselected in each case, and thus unless otherwise specified, fordetermining nonvolatile fractions (nfA, also called solids content orbinder content).

To determine the nonvolatile fraction of the individual components (A)or (B) or (C) or (E) of the coating material, an amount of 1 g of therespective sample of the respective component (A) or (B) or (C) or (E)is applied to a solids-content lid and is heated at 130° C. for 1 h,then cooled to room temperature and weighed again (in accordance withISO 3251). The binder content of the component in wt % is then obtainedcorrespondingly from 100 multiplied by the ratio of the weight of theresidue of the respective sample after drying at 130° C. divided by theweight of the respective sample prior to drying. The nonvolatilefraction was determined, for example, for corresponding polymersolutions or resins present in the coating composition of the invention,in order thereby to be able to adjust and determine the weight fractionof the respective constituent in a mixture of two or more constituentsor in the coating composition as a whole. In the case of commercialcomponents, the binder content of this component may also be equatedwith sufficient accuracy with the stated solids content, unlessotherwise indicated.

The binder content of the coating material composition is in each casethe total binder content of components (A) plus (B) plus (C) plus (E) ofthe coating material composition prior to crosslinking. It iscalculated, in a manner known to the skilled person, from the binderfraction of these components (A) or (B) or (C) or (E) and the amount ofthe respective component (A) or (B) or (C) or (E) that is used in eachcase in 100 parts by weight of the coating material composition: thebinder content of the coating material composition in parts by weight istherefore equal to the sum of the products of the amount of therespective component (A) or (B) or (C) or (E) used in each case in 100parts by weight of the coating material composition, in each casemultiplied by the binder content of the respective component (A) or (B)or (C) or (E) in wt %, and divided in each case by 100.

For the purposes of the invention, the hydroxyl number or OH numberindicates the amount of potassium hydroxide, in milligrams, which isequivalent to the molar amount of acetic acid bound during acetylationof one gram of the constituent in question. For the purposes of thepresent invention, unless otherwise indicated, the hydroxyl number isdetermined experimentally by titration in accordance with DIN 53240-2:2007-11 (Determination of hydroxyl value—Part 2: Method with catalyst).

For the purposes of the invention, the acid number indicates the amountof potassium hydroxide, in 15 milligrams, which is needed to neutralize1 g of the respective constituent. For the purposes of the presentinvention, unless indicated otherwise, the acid number is determinedexperimentally by titration in accordance with DIN EN ISO 2114: 2006-11.

The mass-average (Mw) and number-average (Mn) molecular weight isdetermined for the purposes of the present invention by means of gelpermeation chromatography at 35° C., using a high-pressure liquidchromatography pump and a refractive index detector. The eluent used wastetrahydrofuran containing 0.1 vol % acetic acid, with an elution rateof 1 ml/min. The calibration is carried out using polystyrene standards.

For the purposes of the invention, the glass transition temperature, Tg,is determined experimentally on the basis of DIN 51005 “Thermal Analysis(TA)—Terms” and DIN EN ISO 11357-2 “Thermal analysis—Dynamic ScanningCalorimetry (DSC)”. This involves weighing out a 10 mg sample into asample boat and introducing it into a DSC instrument. The instrument iscooled to the start temperature, after which a 1^(st) and 2^(nd)measurement run is carried out under inert gas flushing (N2) at 50ml/min with a heating rate of 10 K/min, with cooling to the starttemperature again between the measurement runs. Measurement takes placecustomarily in the temperature range from about 50° C. lower than theanticipated glass transition temperature to about 50° C. higher than theglass transition temperature. The glass transition temperature recordedfor the purposes of the present invention, in line with DIN EN ISO11357-2, section 10.1.2, is the temperature in the 2^(nd) measurementrun at which half of the change in the specific heat capacity (0.5 deltacp) is reached. This temperature is determined from the DSC diagram(plot of the flow against the temperature), and is the temperature atthe point of intersection of the midline between the extrapolated baselines, before and after the glass transition, with the measurement plot.

The Polyhydroxyl Group-containing Component (A)

As polyhydroxyl group-containing component (A) it is possible to use allcompounds known to the skilled person which have at least 2 hydroxylgroups per molecule and are oligomeric and/or polymeric. As component(A) it is also possible to use mixtures of different oligomeric and/orpolymeric polyols.

The preferred oligomeric and/or polymeric polyols (A) havenumber-average molecular weights Mn >=300 g/mol, preferably Mn=400-30000 g/mol, more preferably Mn=500-15 000 g/mol, and mass-averagemolecular weights Mw >500 g/mol, preferably between 800 and 100 000g/mol, more particularly between 900 and 50 000 g/mol, as measured bygel permeation chromatography (GPC) against a polystyrene standard.

Preferred as component (A) are polyester polyols, polyacrylate polyolsand/or polymethacrylate polyols, and also copolymers thereof—referred tobelow as polyacrylate polyols; and polyurethane polyols, polysiloxanepolyols, and mixtures of these polyols.

The polyols (A) preferably have an OH number of 30 to 400 mg KOH/g, moreparticularly between 70 and 250 mg KOH/g. In the case of thepoly(meth)acrylate copolymers, the OH number may also be determined withsufficient accuracy by calculation on the basis of the OH-functionalmonomers used.

The polyols (A) preferably have an acid number of between 0 and 30 mgKOH/g.

The glass transition of the polyols; temperatures, in each case measuredby means of differential scanning calorimetry (DSC) to DIN 53765 arepreferably between −150 and 100° C., more preferably between −40° C. and60° C.

Polyurethane polyols are prepared preferably by reaction of oligomericpolyols, more particularly of polyester polyol prepolymers, withsuitable di- or polyisocyanates, and are described in EP-A-1 273 640,for example. Used in particular are reaction products of polyesterpolyols with aliphatic and/or cycloaliphatic di- and/or polyisocyanates.

The polyurethane polyols used with preference in accordance with theinvention have a number-average molecular weight Mn >=300 g/mol,preferably Mn=700-2000 g/mol, more preferably Mn=700-1300 g/mol, andalso, preferably, a mass-average molecular weight Mw >500 g/mol,preferably between 1500 and 3000 g/mol, more particularly between 1500and 2700 g/mol, in each case measured by gel permeation chromatography(GPC) against a polystyrene standard.

Suitable polysiloxane polyols are described in WO-A-01/09260, forexample, and the polysiloxane polyols recited therein can be employedpreferably in combination with further polyols, especially those withrelatively high glass transition temperatures.

Polyhydroxyl group-containing components (A) used with particularpreference are polyester polyols, polyacrylate polyols, polymethacrylatepolyols, polyurethane polyols, or mixtures thereof, and very preferablymixtures of poly(meth)acrylate polyols.

The polyester polyols (A) that are used with preference in accordancewith the invention have a number-average molecular weight Mn >=300g/mol, preferably Mn=400-10 000 g/mol, more preferably Mn=500-5000g/mol, and also, preferably, a mass-average molecular weight Mw >500g/mol, more preferably between 800 and 50 000 g/mol, more particularlybetween 900 and 10 000 g/mol, measured in each case by gel permeationchromatography (GPC) against a polystyrene standard.

The polyester polyols (A) used with preference in accordance with theinvention preferably have an OH number of 30 to 400 mg KOH/g, moreparticularly between 100 and 250 mg KOH/g.

The polyester polyols (A) used with preference in accordance with theinvention preferably have an acid number of between 0 and 30 mg KOH/g.

Suitable polyester polyols are also described in EP-A-0 994 117 andEP-A-1 273 640, for example.

The poly(meth)acrylate polyols (A) used with preference in accordancewith the invention are generally copolymers and preferably have anumber-average molecular weight Mn >=300 g/mol, preferably Mn=500-15 000g/mol, more preferably Mn=900-10 000 g/mol, and also, preferably,mass-average molecular weights Mw of between 500 and 20 000 g/mol, moreparticularly between 1000 and 15 000 g/mol, measured in each case by gelpermeation chromatography (GPC) against a polystyrene standard.

The poly(meth)acrylate polyols (A) preferably have an OH number of 60 to300 mg KOH/g, more particularly between 70 and 250 mg KOH/g, and also anacid number of between 0 and 30 mg KOH/g.

The hydroxyl number (OH number) and the acid number are determined asdescribed above (DIN 53240-2 and DIN EN ISO 2114, respectively).

Monomer units suitable for the poly(meth)acrylate polyols (A) used withpreference in accordance with the invention are identified, for example,in WO2014/016019 on pages 10 and 11 and also in WO2014/016026 on pages11 and 12.

Used in particular in accordance with the invention are coating materialcompositions (K) which comprise as component (A) one or morepoly(meth)acrylate polyols (A1) having a glass transition temperature ofbetween −100 and <30° C., preferably below 10° C., more particularlybetween −60° C. to +5° C., and more preferably between −30° C. and <0°C. (measured by differential scanning calorimetry (DSC) to DIN 53765).Additionally the coating material compositions (K) may further compriseone or more different poly(meth)acrylate polyols (A2), preferablypoly(meth)acrylate polyols (A2) which have a glass transitiontemperature of 10 to 50° C. (differential scanning calorimetry (DSC) toDIN 53765). The glass transition temperature may initially also beestimated theoretically by the skilled person with the aid of the Foxequation (III) below, but is then to be determined experimentally asdescribed above:

$\begin{matrix}{{1/T_{g}} = {\overset{n = x}{\sum\limits_{n = 1}}{W_{n}/T_{gn}}}} & ({III})\end{matrix}$where

T_(g)=glass transition temperature of the polyacrylate orpolymethacrylate, x=number of different copolymerized monomers,W_(n)=weight fraction of the nth monomer, T_(gn)=glass transitiontemperature of the homopolymer of the nth monomer.

The component (A) preferably comprises at least one (meth)acrylatecopolymer which is obtainable by copolymerizing

-   (a) 10 to 80 wt %, preferably 20 to 50 wt %, of a    hydroxyl-containing ester of acrylic acid or mixtures of these    monomers,-   (b) 0 to 30 wt %, preferably 0 to 15 wt %, of a non-(a)    hydroxyl-containing ester of methacrylic acid or of a mixture of    such monomers,-   (c) 5 to 90 wt %, preferably 20 to 70 wt %, of a non-(a) and non-(b)    aliphatic or cycloaliphatic ester of (meth)acrylic acid having at    least 4 carbon atoms in the alcohol residue, or of a mixture of such    monomers,-   (d) 0 to 5 wt %, preferably 0.5 to 3.5 wt %, of an ethylenically    unsaturated carboxylic acid or of a mixture of ethylenically    unsaturated carboxylic acids,-   (e) 0 to 50 wt %, preferably 0 to 20 wt %, of a vinylaromatic or of    a mixture of such monomers, and-   (f) 0 to 50 wt %, preferably 0 to 35 wt %, of an ethylenically    unsaturated monomer other than (a), (b), (c), (d), and (e), or of a    mixture of such monomers, the sum of the weight fractions of    components (a), (b), (c), (d), (e), and (f) always making 100 wt %,    and also optionally one or more (meth)acrylate copolymers different    therefrom.    Component (B)

The coating materials of the invention comprise a component (B) havingon average at least one isocyanate group and having on average at leastone hydrolyzable silane group. The coating materials of the inventionpreferably comprise a component (B) having on average at least one freeisocyanate group.

The di- and/or polyisocyanates that serve as parent structures for thecomponent (B) used with preference in accordance with the invention arepreferably conventional substituted or unsubstituted aromatic,aliphatic, cycloaliphatic and/or heterocyclic polyisocyanates, morepreferably aliphatic and/or cycloaliphatic polyisocyanates. Additionallypreferred are the polyisocyanate parent structures derived from analiphatic and/or cycloaliphatic diisocyanate of this kind bydimerization, trimerization, biuret formation, uretdione formation,allophanate formation and/or isocyanurate formation.

The di- and/or polyisocyanates serving as parent structures for thecomponent (B) used with preference in accordance with the invention aredescribed for example in WO2014/016019 on pages 12 and 13 and also inWO2014/016026 on pages 13 and 14.

Di- and/or polyisocyanates serving with particular preference as parentstructures for the component (B) used with preference in accordance withthe invention are hexamethylene 1,6-diisocyanate, isophoronediisocyanate, and 4,4′-methylenedicyclohexyl diisocyanate, or mixturesof these isocyanates, and/or one or more polyisocyanate parentstructures derived from such an isocyanate by dimerization,trimerization, biuret formation, uretdione formation, allophanateformation and/or isocyanurate formation. More particularly thepolyisocyanate parent structure is 1,6-hexamethylene diisocyanate,1,6-hexamethylene diisocyanate isocyanurate, 1,6-hexamethylenediisocyanate uretdione, isophorone diisocyanate, isophorone diisocyanateisocyanurate, or a mixture of two or more of these polyisocyanates, morepreferably 1,6-hexamethylene diisocyanate isocyanurate.

In a further embodiment of the invention, the di- and/or polyisocyanatesthat serve as parent structures for the component (B) used withpreference in accordance with the invention are polyisocyanateprepolymers with urethane structural units, which are obtained byreaction of polyols with a stoichiometric excess of aforesaidpolyisocyanates. Polyisocyanate prepolymers of this kind are describedfor example in U.S. Pat. No. 4,598,131.

Component (B) comprises on average at least one isocyanate group andalso, additionally, on average

at least one structural unit (I) of the formula (I)—NR—(X—SiR″_(x)(OR′)_(3-x))  (I),and/orat least one structural unit (II) of the formula (II)—N(X—SiR″_(x)(OR′)_(3-x))_(n)(X′—SiR″_(y)(OR′)_(3-y))_(m)  (II),where

R=hydrogen, alkyl, cycloalkyl, aryl, or aralkyl, it being possible forthe carbon chain to be interrupted by nonadjacent oxygen, sulfur, or NRagroups, with Ra=alkyl, cycloalkyl, aryl or aralkyl,

-   R′=hydrogen, alkyl, or cycloalkyl, it being possible for the carbon    chain to be interrupted by nonadjacent oxygen, sulfur, or NRb    groups, with Rb=alkyl, cycloalkyl, aryl or aralkyl, preferably    R′=ethyl and/or methyl,-   X, X′=linear and/or branched alkylene or cycloalkylene radical    having 1 to 20 carbon atoms, preferably X, X′=alkylene radical    having 1 to 4 carbon atoms,-   R″=alkyl, cycloalkyl, aryl, or aralkyl, it being possible for the    carbon chain to be interrupted by nonadjacent oxygen, sulfur, or NRc    groups, with Rc=alkyl, cycloalkyl, aryl or aralkyl, preferably    R″=alkyl radical, more particularly having 1 to 6 C atoms,-   n=0 to 2, m=0 to 2, m+n=2, and x, y=0 to 2.

Preferably, additionally, component (B) comprises has on average atleast one isocyanate group and also on average at least one structuralunit (I) of the formula (I) and on average at least one structural unit(II) of the formula (II).

The respective preferred alkoxy radicals (OR′) may be alike ordifferent; critical for the construction of the radicals, however, isthe extent to which they influence the reactivity of the hydrolyzablesilane groups. Preferably R′ is an alkyl radical, more particularlyhaving 1 to 6 C atoms. Particularly preferred radicals R′ are thosewhich raise the reactivity of the silane groups, i.e., which representgood leaving groups. A methoxy radical is therefore preferred over anethoxy radical, which is preferred in turn over a propoxy radical. Withparticular preference, therefore, R′=ethyl and/or methyl, moreparticularly methyl.

The reactivity of organofunctional silanes may also be considerablyinfluenced, furthermore, by the length of the spacers X, X′ betweensilane functionality and organic functional group serving for reactionwith the constituent to be modified. Exemplary of this are the“alpha”-silanes, which are available from Wacker and in which there is amethylene group between Si atom and functional group, rather than thepropylene group present in the case of “gamma”-silanes.

Component (B) as preferably employed consists generally of a mixture ofdifferent compounds and has only on average at least one structural unit(I) of the formula (I), and/or at least one structural unit (II) of theformula (II), and on average at least one, preferably more than one,isocyanate group. Very preferably, component (B) has on average at leastone structural unit (I) of the formula (I) and at least one structuralunit (II) of the formula (II), and on average more than one isocyanategroup.

The component (B) consists more particularly of a mixture of at leastone compound (B1) having more than one isocyanate group and nostructural units (I) and (II), with at least one compound (B2) which hasat least one isocyanate group and at least one structural unit (I), andwith at least one compound (B3) which has at least one isocyanate groupand at least one structural unit (II), and/or with at least one compound(B4) which has at least one structural unit (I) and at least onestructural unit (II), and/or with at least one compound (B5) which hasat least one isocyanate group and at least one structural unit (I) andat least one structural unit (II).

The components (B) used with preference in accordance with the inventionand functionalized with the structural units (I) and/or (II) areobtained in particular by reaction of—preferably aliphatic—di and/orpolyisocyanates, and/or the polyisocyanates derived therefrom bytrimerization, dimerization, urethane formation, biuret formation,uretdione formation and/or allophanate formation, with at least onecompound of the formula (Ia)H—NR—(X—SiR″_(x)(OR′)_(3-x))  (Ia),

and/or with at least one compound of the formula (IIa)HN(X—SiR″_(x)(OR′)_(3-x))_(n)(X′—SiR″_(y)(OR′)_(3-y))_(m)  (IIa),

the substituents having the definition stated above.

The component (B) used with particular preference in accordance with theinvention and functionalized with the structural units (I) and (II) isobtained correspondingly by reaction of polyisocyanates with at leastone compound of the formula (Ia) and with at least one compound of theformula (IIa).

In this context it is possible, for the preparation of component (B), toreact directly the total amount of the di- and/or polyisocyanate used inpreparing component (B) with the mixture of at least one compound (Ia)and at least one compound (IIa). Furthermore, to prepare component (B),it is also possible to react the total amount of the di- and/orpolyisocyanate used in preparing component (B) first with at least onecompound (Ia) and thereafter with at least one compound (IIa).

Furthermore, for preparing component (B), it is possible first to reactonly part of the total amount of the di- and/or polyisocyanate used inpreparing component (B) with the mixture of at least one compound (Ia)and at least one compound (IIa), and subsequently to add the remainingpart of the total amount of the di- and/or polyisocyanate used inpreparing component (B).

Lastly, for preparing component (B), it is possible first to react onlypart of the total amount of the di- and/or polyisocyanate used inpreparing component (B) separately with at least one compound (Ia), andto react another part of the total amount of the di- and/orpolyisocyanate used in preparing component (B) separately with at leastone compound (IIa), and optionally, subsequently, to add any remainingresidual part of the total amount of the di- and/or polyisocyanate usedin preparing component (B). It will be appreciated here that allconceivable hybrid forms of the stated reactions are possible for thepreparation of component (B).

Preferably, however, component (B) is prepared by alternatively reactingthe total amount of the di- and/or polyisocyanate used in preparingcomponent (B) with the mixture of at least one compound (Ia) and atleast one compound (IIa)

or

mixing a part of the total amount of the di- and/or polyisocyanate usedin preparing component (B) with a component which has been fullysilanized with the compounds (Ia) and (IIa) and is therefore free ofisocyanate groups

and/or

mixing a part of the total amount of the di- and/or polyisocyanate usedin preparing component (B) with a component (I) which has been fullysilanized with the compound (Ia) and is therefore free of isocyanategroups, and with a component (II) which has been fully silanized withthe compound (IIa) and is therefore free of isocyanate groups.

Inventively preferred compounds (IIa) arebis(2-ethyltrimethoxysilyl)amine, bis(3-propyltrimethoxysilyl)amine,bis(4-butyltrimethoxysilyl)amine, bis(2-ethyltriethoxysilyl)amine,bis(3-propyltriethoxysilyl)amine and/or bis(4-butyltriethoxysilyl)amine.Especially preferred is bis(3-propyltrimethoxysilyl)amine. Aminosilanesof this kind are available for example under the brand name DYNASYLAN®from Evonik or Silquest® from OSI.

Inventively preferred compounds (Ia) are aminoalkyl-trialkoxysilanes,such as preferably 2-aminoethyltrimethoxysilane,2-aminoethyltriethoxysilane, 3-aminopropyltrimethoxy-silane,3-aminopropyltriethoxysilane, 4-aminobutyltrimethoxysilane,4-aminobutyltri-ethoxysilane. Particularly preferred compounds (Ia) areN-(2-(trimethoxysilyl)ethyl)alkylamines,N-(3-(tri-methoxysilyl)propyl)alkylamines,N-(4-(trimethoxysil-yl)butyl)alkylamines,N-(2-(triethoxysilyl)ethyl)alkylamines,N-(3-(triethoxysilyl)propyl)alkylamines and/orN-(4-(triethoxysilyl)butyl)alkylamines. Especially preferred isN-(3-(trimethoxysilyl)propyl)butylamine. Aminosilanes of this kind areavailable for example under the brand name DYNASYLAN® from Evonik orSilquest® from OSI.

In component (B) preferably between 5 and 75 mol %, more particularlybetween 10 and 60 mol %, preferably between 15 and 50 mol %, of theisocyanate groups originally present have undergone reaction to formstructural units (I) and/or (II), preferably to form structural units(I) and (II).

In component (B), in particular the total amount of bissilane structuralunits (II) is between 5 and 100 mol %, preferably between 10 and 98 mol%, more preferably between 20 and 90 mol %, very preferably between 30and 80 mol %, based in each case on the entirety of the structural units(I) plus (II), and the total amount of monosilane structural units (I)is between 95 and 0 mol %, preferably between 90 and 2 mol %, morepreferably between 80 and 10 mol %, more preferably between 70 and 20mol %, based in each case on the entirety of the structural units (I)plus (II).

In component (B), more preferably, between 5 and 55 mol %, preferablybetween 9.8 and 50 mol %, more preferably 13.5 and 45 mol % of theisocyanate groups originally present have undergone reaction to formbissilane structural units of the formula (II).

The Hydroxyl Group-containing Component (C)

Optionally, as well as the polyhydroxyl group-containing component (A),the coating material compositions of the invention may comprise one ormore monomeric, hydroxyl group-containing components (C) that aredifferent from component (A). These components (C) preferably occupy afraction of 0 to 10 wt %, more preferably of 0 to 5 wt %, based in eachcase on the binder content of the coating material composition.

Low molecular mass polyols, especially diols, are used as hydroxylgroup-containing component (C). Examples of suitable polyols (C) aredescribed in WO 2014/016019 on page 12 and also in WO 2014/016026 onpage 13. Low molecular means polyols (C) of this kind are preferablyadmitted in minor amounts to the polyol component (A).

The Catalyst (D)

It is essential to the invention that phosphorus- andnitrogen-containing catalysts are used as catalyst (D). Mixtures of twoor more different catalysts (D) may also be used here.

Examples of suitable phosphorus- and nitrogen-containing catalysts (D)are the amine adducts of optionally substituted phosphonic diesters andoptionally substituted diphosphonic diesters, preferably from the groupconsisting of amine adducts of optionally substituted acyclic phosphonicdiesters, or optionally substituted cyclic phosphonic diesters, ofoptionally substituted acyclic diphosphonic diesters, and of optionallysubstituted cyclic diphosphonic diesters. Catalysts of these kinds aredescribed for example in German patent application DE-A-102005045228.

Used in particular, however, are amine adducts of optionally substitutedphosphoric monoesters and/or amine adducts of optionally substitutedphosphonic diesters, preferably from the group consisting of amineadducts of acyclic phosphoric monoesters and diesters and of cyclicphosphoric monoesters and diesters.

Especially preferred for use as catalyst (D) are amine-blockedethylhexyl phosphates and amine-blocked phenyl phosphates, verypreferably amine-blocked bis(2-ethylhexyl) phosphate.

Examples of amines with which the phosphoric esters are blocked are, inparticular, tertiary amines, examples being bicyclic amines, such asdiazabicyclooctane (DABCO), diazabicyclononene (DBN),diazabicycloundecene (DBU), and/or aliphatic triamines, moreparticularly dimethyldodecylamine or triethylamine, for example. Withpreference the phosphoric esters are blocked using tertiary amines whichensure high activity of the catalyst under the curing conditions. Usedwith very particular preference, especially at low curing temperaturesof not more than 90° C., to block the phosphoric esters are bicyclicamines, especially diazabicyclo[2.2.2]octane (DABCO), and/ortriethylamine.

Especially preferred for use as catalyst (D)diazobicyclo[2.2.2]octane-blocked ethylhexyl phosphates.

Certain amine-blocked phosphoric acid catalysts are also availablecommercially (e.g., Nacure products from King Industries).

The catalyst (D) or—if a mixture of two or more catalysts (D) isused—the catalysts (D) are used preferably in fractions of 0.1 to 15 wt%, more preferably in fractions of 0.5 to 10.0 wt %, very preferably infractions of 0.75 to 8.0 wt %, based on the binder content of thecoating material composition. A lower activity on the part of thecatalyst may be partly compensated by correspondingly higher quantitiesemployed.

The Catalyst (Z)

It is essential to the invention that the coating material composition(K) additionally further comprises at least one catalyst (Z), differentfrom the accelerator (R) and from the catalyst (D), for the reaction ofthe hydroxyl groups with the isocyanate groups.

The catalyst (Z) for the reaction between the hydroxyl groups ofcomponent (A) and the isocyanate groups of component (B) is selectedfrom the group of zinc carboxylates and bismuth carboxylates and also ofaluminum, zirconium, titanium and/or boron chelates, and/or ofinorganic, tin-containing catalysts, and of mixtures thereof.

Suitable more particularly as organic, tin-containing catalysts (Z) aretin compounds that contain no tin-carbon bonds, but instead contain onlycarbon atoms bonded via heteroatoms, more particularly by oxygen,sulfur, or nitrogen, preferably via oxygen.

Particularly preferred as inorganic, tin-containing catalysts (Z) arecyclic tin(IV) compounds having alkyl radicals and/or cycloalkylradicals and/or aryl radicals and/or arylalkyl radicals bondedexclusively via oxygen atoms and/or nitrogen atoms and/or sulfur atoms,more particularly via oxygen atoms.

Inorganic, tin-containing catalysts (Z) are described for example in WO2014/048879, page 4, line 20 to page 10, line 34, and page 15, line 1,to page 16, table 1, and also in WO 2014/048854, page 2, line 32, topage 9, line 15, and page 14, line 1 to page 15, table 1, and in EP-B1-2493 948, page 2, line 53, to page 6, line 54, and page 9, catalyst 4 to8, and page 10, catalyst 10.

Catalysts (Z) based on aluminum, zirconium, titanium and/or boronchelates are known and are described for example in WO06/042585, page10, lines 4 to 21. The compounds which form chelate ligands are organiccompounds having at least two functional groups which are able tocoordinate to metal atoms or metal ions. These functional groups areusually electron donors, which give up electrons to metal atoms or metalions as electron acceptors. Suitable in principle are all organiccompounds of the stated type, provided they do not deleteriouslyinfluence, let alone completely prevent, the crosslinking of the coatingmaterial compositions. Use may be made as catalysts, for example, of thealuminum chelate and zirconium chelate complexes, as described forexample in the American patent U.S. Pat. No. 4,772,672 A, column 8, line1, to column 9, line 49. Preference is given to aluminum and/orzirconium and/or titanium chelates, such as aluminum ethyl acetoacetateand/or zirconium ethyl acetoacetate, for example.

Catalysts (Z) based on the zinc and bismuth carboxylates are likewiseknown. Used in particular as catalysts (Z) are zinc(II) biscarboxylatesand bismuth(III) triscarboxylates in which the carboxylate radical isselected from the group of carboxylate radicals of aliphatic linearand/or branched, optionally substituted monocarboxylic acids having 1 to24 C atoms in the alkyl radical, and/or of aromatic, optionallysubstituted monocarboxylic acids having 6 to 12 C atoms in the arylradical. The carboxylate radical largely determines the solubility ofthe resulting catalyst in the coating components used. Examples ofsuitable catalysts (Z) include the Zn(II) and Bi(III) salts of aceticacid and of formic acid.

Used with particular preference as catalyst (Z) are the Bi(III) salts ofbranched fatty acids, and especially the Bi(III) salts of branched C3 toC24 fatty acids, preferably branched C4 to C20 fatty acids, morepreferably branched C6 to C16 fatty acids, and very preferably from thegroup of octanoic acids, especially 2-ethylhexanoic acid, and ofdecanoic acids, especially neodecanoic acid. Especially preferred foruse as catalyst (Z) is the Bi(III) salt of branched C3 to C24 fattyacids. The Bi(III) salt of branched fatty acids here may also be presentin the form of a polynuclear complex.

Certain Zn(II) and Bi(III) salts of branched fatty acids are alsoavailable commercially (e.g., Borchi® Kat products from Lanxess Corp.and K-Kat® products from King Industries). Mention may be made, forexample, as particularly suitable catalysts (Z), of those under the nameCoscat® 83 from C.H. Erbslöh GmbH & Co. KG, based on bismuthtrisneodecanoate; under the name Borchi® Kat 24 from Lanxess Corp.,based on bismuth carboxylate; under the name K-Kat® 348 from KingIndustries, based on bismuth carboxylate; and under the name K-Kat®XC-8203 from King Industries, likewise based on bismuth carboxylate.

The catalyst (Z) or—if a mixture of two or more catalysts (Z) isused—the catalysts (Z) are used preferably in fractions of 0.005 to 1.0wt %, more preferably in fractions of 0.02 to 0.75 wt %, very preferablyin fractions of 0.05 to 0.5 wt %, based on the binder content of thecoating material composition. A lower activity on the part of thecatalyst here can be partly compensated by correspondingly higherquantities employed.

The Accelerator (R)

Especially if the inventively employed coating material compositions arecured at relatively low temperatures of up to 100° C., it is essentialto the invention that the coating material compositions include at leastone accelerator (R). Accelerators (R) used may be any components thatare different from the catalyst (D) and the catalyst (Z) and thataccelerate the reaction of the isocyanate groups of component (B) withthe hydroxyl groups of component (A) and optionally (C), and/oraccelerate the reaction of the alkoxysilane groups. Especially suitableas accelerators (R) are inorganic acids and/or organic acids and/orpartial esters of inorganic acids and/or partial esters of organicacids. Acids used are, in particular, sulfonic acids, such asdodecylbenzenesulfonic acid and toluenesulfonic acid, monomeric aromaticcarboxylic acids, such as benzoic acid, tert-butylbenzoic acid,3,4-dihydroxybenzoic acid, salicylic acid and/or acetylsalicylic acid,for example, especially benzoic acid, alkylphosphonic acids,dialkylphosphinic acids, phosphonic acid, diphosphonic acid, phosphoricacid, partial esters of phosphoric acid, and the like.

Preferred for use as accelerators (R) are phosphorus-containing acidsand/or partial esters of phosphorus-containing acids, such as, forexample, alkylphosphonic acids, dialkylphosphinic acids, phosphonicacid, diphosphonic acid, phosphinic acid, optionally substituted acyclicphosphoric monoesters and/or optionally substituted cyclic phosphoricmonoesters and/or optionally substituted acyclic phosphoric diestersand/or optionally substituted acyclic phosphoric diesters.

Particularly preferred for use are optionally substituted acyclicphosphoric monoesters and/or optionally substituted cyclic phosphoricmonoesters and/or optionally substituted acyclic phosphoric diestersand/or optionally substituted acyclic phosphoric diesters, especiallyacyclic phosphoric diesters and cyclic phosphoric diesters. Use is madehere more particularly of partial esters (R) of phosphoric acid, of thegeneral formula (V):

where the radicals R₁₀ and R₁₁ are selected from the group consistingof:

-   -   substituted and unsubstituted alkyl having 1 to 20, preferably 2        to 16, and more particularly 2 to 10 carbon atoms, cycloalkyl        having 3 to 20, preferably 3 to 16, and more particularly 3 to        10 carbon atoms, and aryl having 5 to 20, preferably 6 to 14,        and more particularly 6 to 10 carbon atoms,    -   substituted and unsubstituted alkylaryl, arylalkyl,        alkylcycloalkyl, cycloalkylalkyl, arylcycloalkyl,        cycloalkylaryl, alkylcycloalkylaryl, alkylarylcycloalkyl,        arylcycloalkylalkyl, arylalkylcycloalkyl, cycloalkylalkylaryl,        and cycloalkylarylalkyl, where the alkyl, cycloalkyl, and aryl        groups present therein each contain the number of carbon atoms        set out above, and    -   substituted and unsubstituted radical of the aforementioned        kind, comprising at least one, more particularly one, heteroatom        selected from the group consisting of oxygen atom, sulfur atom,        nitrogen atom, phosphorus atom, and silicon atom, more        particularly oxygen atom, sulfur atom, and nitrogen atom, and        additionally one of the radicals, R₁₀ or R₁₁, may also be        hydrogen.

Especially preferred for use are partial esters (R) of phosphoric acid,of the general formula (V), in which the radicals R₁₀ and R₁₁ areselected from the group consisting of substituted and unsubstitutedalkyl having 1 to 20, preferably 2 to 16, and more particularly 2 to 10carbon atoms, cycloalkyl having 3 to 20, preferably 3 to 16, and moreparticularly 3 to 10 carbon atoms, and aryl having 5 to 20, preferably 6to 14, and more particularly 6 to 10 carbon atoms, and especiallybis(2-ethylhexyl) phosphate and/or bisphenyl phosphate.

The accelerator (R) or—if a mixture of 2 or more accelerators (R) isused—the accelerators (R) are used preferably in fractions of 0.05 to10.0 wt %, more preferably in fractions of 0.1 to 5.0 wt %, verypreferably in fractions of 0.5 to 2.5 wt %, based on the binder contentof the coating material composition.

Catalyst (D), catalyst (Z), and accelerators (R) are used in the coatingmaterial compositions of the invention more particularly in amounts suchthat the total amount of catalyst (D) plus catalyst (Z) plus accelerator(R) is between 0.2 and 21 wt %, preferably between 0.6 and 11 wt %, andmore preferably between 1.1 and 8.1 wt %, based in each case on thebinder content of the coating material composition.

Especially preferred coating material compositions are those in which

-   i. the phosphorus- and nitrogen-containing catalyst (D) is selected    from the group of the adducts of diazabicyclo[2.2.2]octane,    dimethyldodecylamine and/or triethylamine with acyclic phosphoric    monoesters, with cyclic phosphoric monoesters, with acyclic    phosphoric diesters and/or with cyclic phosphoric diesters,-   ii. the catalyst (Z) is selected from the group of the Bi(III) salts    of branched C3 to C24 fatty acids, and-   iii. the reaction accelerator (R) is selected from the group of    acyclic phosphoric diesters and of cyclic phosphoric diesters.    The Combination of Components (A), (B), Optionally (C), (D), (Z),    (R), and Further Components of the Coating Material Compositions

For the 2-component (2K) coating material compositions that areparticularly preferred in accordance with the invention, a film-formingcomponent, comprising the polyhydroxyl group-containing component (A)and also further components described below, is mixed in a conventionalway with a further film-forming component, comprising the isocyanategroup-combining component (B) and also, optionally, further of thecomponents described below, this mixing taking place shortly before thecoating material is applied; here, generally, the film-forming componentwhich comprises component (A) comprises the catalyst (D), the catalyst(Z), and the accelerator (R) and also a part of the solvent.

The polyhydroxyl group-containing component (A) may be present in asuitable solvent. Suitable solvents are those which allow sufficientsolubility of the polyhydroxyl group-containing component.

Besides components (A), (B), and optionally (C), there may also befurther binders (E) used, which are able to react and form network nodespreferably with the hydroxyl groups of the poly(meth)acrylate (A) and/orwith the free isocyanate groups of component (B) and/or with thealkoxysilyl groups of the component (B).

As component (E) it is possible for example to use amino resins and/orepoxy resins. Those contemplated are the customary and known aminoresins for example in WO 2014/016026 on pages 26 and 27.

In general such components (E) are used in fractions of up to 40 wt %,preferably of up to 30 wt %, more preferably of up to 25 wt %, verypreferably of 0 to 15 wt %, based in each case on the binder content ofthe coating material composition of the invention.

Preference is given in accordance with the invention to using coatingmaterial compositions which comprise from 20.0 to 80.0 wt %, preferablyfrom 30.0 to 70.0 wt %, based in each case on the binder content of thecoating material composition, of at least one polyhydroxylgroup-containing component (A), more particularly at least onepolyhydroxyl group-containing polyacrylate (A) and/or at least onepolyhydroxyl group-containing polymethacrylate (A).

Preference is given in accordance with the invention to using coatingmaterial compositions which contain from 80.0 to 20.0 wt %, preferablyfrom 70.0 to 30.0 wt %, based in each case on the binder content of thecoating material composition, of component (B).

The coating material compositions preferably comprise component (C) in afraction of 0 to 20 wt %, more preferably of 0 to 10 wt %, verypreferably of 1 to 5 wt %, based in each case on the binder content ofthe coating material composition.

The weight fractions of component (A), of the optionally employedcomponent (C), and of component (B) are preferably selected such thatthe molar equivalents ratio of the hydroxyl groups of the polyhydroxylgroup-containing components (A) plus optionally (C) to the isocyanategroups of component (B) is between 1:0.5 and 1:1.5, preferably between1:0.8 and 1:1.2, more preferably between 1:0.9 and 1:1.1.

The polyhydroxyl group-containing component (A), the polyethoxylcomponent (C), and/or the isocyanate component (B) may be present in asuitable solvent. Suitable solvents (L) for the coating materials of theinvention are especially those which in the coating material arechemically inert toward the components (A), (B), and optionally (C) andwhich also do not react with (A), optionally (C), and (B) during thecuring of the coating material. Mention may be made in particular hereof aprotic solvents. Examples of such aprotic solvents are aliphaticand/or aromatic hydrocarbons, ketones, esters, ethers, or mixtures ofthe aforementioned solvents. The aprotic solvents or solvent mixturespreferably have a water content of not more than 1 wt %, more preferablynot more than 0.5 wt %, based on the solvent.

The solvent or solvents are used preferably in the coating materialcompositions of the invention in an amount such that the binder contentof the coating material composition is at least 50 wt %, more preferablyat least 60 wt %. It should be borne in mind here that generallyspeaking, as the solids content becomes higher, the viscosity of thecoating material composition goes up, and the leveling of the coatingmaterial composition and therefore the overall visual impressionconveyed by the cured coating become poorer.

The coating material compositions of the invention preferably furthercomprise at least one customary and known coatings additive (F),different from components (A), (B), (D), (Z), (R), optionally (C), andoptionally (E), in effective amounts, i.e., in amounts preferably up to20 wt %, more preferably of 0 up to 10 wt %, based in each case on thebinder content of the coating material composition.

Examples of suitable coatings additives (F) are as follows:

-   -   radical scavengers;    -   slip additives;    -   polymerization inhibitors;    -   defoamers;    -   reactive diluents other than components (A) and (C), more        particularly reactive diluents which become reactive only        through reaction with other constituents and/or with water, such        as Incozol or aspartic esters, for example;    -   wetting agents other than components (A) and (C), such as        siloxanes, fluorine-containing compounds, carboxylic monoesters,        phosphoric esters, polyacrylic acids and copolymers thereof, or        polyurethanes;    -   adhesion promoters;    -   leveling agents;    -   rheological assistants, based for example on customary        hydrophilic and/or hydrophobic fumed silica, such as various        Aerosil® products, or customary urea-based rheological        assistants;    -   film-forming assistants such as cellulose derivatives;    -   fillers such as, for example, nanoparticles based on silicon        dioxide, aluminum oxide, or zirconium oxide; for further        details, refer to Römpp Lexikon “Lacke und Druckfarben” Georg        Thieme Verlag, Stuttgart, 1998, pages 250 to 252;    -   flame retardants.

Particularly preferred coating material compositions are those whichcomprise

30.0 to 70.0 wt %, based on the binder content of the coating materialcomposition, of at least one polyhydroxyl group-containing polyacrylate(A) and/or at least one polyhydroxyl group-containing polymethacrylate(A) and/or at least one polyhydroxyl group-containing polyester polyol(A) and/or one polyhydroxyl group-containing polyurethane (A), 70.0 to30.0 wt %, based on the binder content of the coating materialcomposition, of at least one component (B), having on average at leastone isocyanate group and having on average at least one hydrolyzablesilane group,

-   0 to 10 wt %, based on the binder content of the coating material    composition, of the at least one hydroxyl group-containing component    (C),-   0 up to 15 wt %, based on the binder content of the coating material    composition, of at least one amino resin (E),-   0.5 to 10 wt %, based on the binder content of the coating material    composition of the invention, of at least one catalyst (D),-   0.02 to 0.55 wt %, based on the binder content of the coating    material composition of the invention, of at least one catalyst (Z),-   0.1 to 5.0 wt %, based on the binder content of the coating material    composition of the invention, of at least one accelerator (R), and-   0 to 10 wt %, based on the binder content of the coating material    composition, of at least one customary and known coatings additive    (F).

More particularly, the inventively employed coating materials aretransparent coating materials, preferably clearcoat materials. Theinventively employed coating materials therefore contain no pigments, orcomprise only organic transparent dyes or transparent pigments.

In a further embodiment of the invention, the inventively employedcoating material composition may also comprise further pigments and/orfillers and may serve for producing pigmented topcoats and/or pigmentedundercoats or primer-surfacers, more particularly pigmented topcoats.The pigments and/or fillers employed for these purposes are known to theskilled person. The pigments are customarily used in an amount such thatthe pigment-to-binder ratio is between 0.05:1 and 1.5:1, based in eachcase on the binder content of the coating material composition.

The transparent coating materials used with preference in accordancewith the invention may be applied to pigmented basecoat materials.Preferably, the applied basecoat material is initially dried, meaningthat at least part of the organic solvent and/or of the water is removedfrom the basecoat film in an evaporation phase. Drying takes placepreferably at temperatures from room temperature to 80° C. After thedrying, the transparent coating material composition is applied.Subsequently, the two-coat paint system is baked at temperatures of 20to 200° C. for a time of 1 min up to 10 h, employing preferably lowertemperatures, between 20 and 100° C., preferably between 30 and 90° C.,and correspondingly longer curing times, of up to 60 min.

The invention accordingly also provides multicoat color and/or effectpaint systems composed of at least one pigmented basecoat and at leastone clearcoat arranged thereon, wherein the clearcoat has been producedfrom the coating material composition of the invention.

The basecoat materials are known to the skilled person. Not onlywater-thinable basecoat materials but also basecoat materials based onorganic solvents can be used. These basecoat materials customarilycomprise one or more binders, one or more pigments, optionally one ormore crosslinking agents, one or more organic solvents, and customarilyauxiliaries and adjuvants, and also, in the case of waterborne basecoatmaterials, water as additional solvent.

Suitable basecoat materials are described for example in EP-A-0 692 007and in the documents recited therein in column 3, lines 50 ff.

Because the coatings of the invention produced from the coatingmaterials of the invention also exhibit outstanding adhesion to alreadycured electrocoats, primer-surfacer coats, basecoats, or customarily andknown clearcoats, they are outstanding suitable not only for use inautomotive OEM finishing but also for automotive refinishing and/or forthe coating of parts for installation in or on automobiles, and/or forthe coating of commercial vehicles.

The application and curing of the coating material compositions takeplace in accordance with the customary and known methods, as describedfor example in WO 2014/016026 on pages 29 and 33.

The coating material compositions and paint systems, especially theclearcoat systems, are used more particularly in the technologically andesthetically particularly demanding field of automotive OEM finishingand for the coating of plastics parts for installation in or onautomobile bodies, more particularly for top-class automobile bodies,such as, for example, for the production of roofs, trunk lids andtailgates, engine hoods, wheel arches, fenders, spoilers, sills,protective strips, side trim, and the like, and also for automotiverefinishing and for commercial vehicles, such as, for example, oftrucks, chain-driven construction vehicles, such as crane vehicles,wheel loaders, and concrete mixers, for example, buses, rail vehicles,watercraft, aircraft, and also agricultural equipment such as tractorsand combine harvesters, and parts thereof.

The plastics parts consist customarily of ASA, polycarbonates, blends ofASA and polycarbonates, polypropylene, polymethyl methacrylates, orimpact-modified polymethyl methacrylates, more particularly of blends ofASA and polycarbonates, preferably with a polycarbonate fraction >40%,more preferably >50%.

In a further preferred embodiment of the invention, the coating materialcomposition of the invention is used as a transparent clearcoat materialfor the coating of plastics substrates, more particularly of plasticsparts for installation in or on vehicles. The plastics parts forinstallation are preferably likewise coated in a multistage coatingprocess, in which an optionally precoated substrate or a substratepretreated for better adhesion of the subsequent coatings (e.g.,flaming, corona or plasma treatment of the substrate) is coated firstwith a pigmented basecoat and thereafter with a coat of the coatingmaterial composition of the invention.

The present invention is now described in more detail using the examplesbelow. All figures in these examples are weight figures, unlessexpressly indicated otherwise.

Preparation of a Polyacrylates Polyol (A1)

A steel reactor with monomer feed and initiator feed, thermometer, oilheating, and reflux condenser is charged with 26.63 g of Solventnaphtha®(commercially available aromatic solvent from DHC Solvent Chemic GmbH)and this initial charge is heated to 40° C. Then a mixture M1 consistingof 2.94 g of Solventnaphtha® and 1.54 g of di-tert-butyl peroxide isadded dropwise with stirring. The metering rate is set such that theaddition of the mixture M1 is over after 6.75 hours. 15 minutes afterthe start of the addition of the mixture M1, the mixture M2, consistingof 8.21 g of styrene, 20.2 g of tert-butyl acrylate, 12.62 g ofbutanediol monoacrylate, 8.84 g of n-butyl methacrylate, 12.64 g ofhydroxyethyl acrylate, and 0.63 g of acrylic acid, is added dropwise.The metering rate is set so that the addition of the mixture M2 is overafter 6 hours. When the addition of mixture M1 is over, the mixture isheld at 140° C. for a further 2 hours and then cooled to below 100° C.The mixture is then diluted with 5.79 g of Solventnaphtha® (commerciallyavailable aromatic solvent mixture from DHC Solvent Chemic GmbH). Theresulting solution of the polyacrylates polyol (A1) has a solids contentof 65% (1 hour, 130° C. forced air oven), a viscosity of 18.5 dPas (ICIcone/plate viscometer 23° C.), an OH number of 175 mg KOH/g, and an acidnumber of 8-12 mg KOH/g.

Preparation of the Curing Agent Solution (B1)

A 250 ml three-neck flask with stirring magnetic, internal thermometer,and dropping funnel is charged with a mixture of 51.6 g of a trimerizedisocyanurate based on hexamethyl-1,6-diisocyanate (Desmodur® N 3600,Bayer, Leverkusen) and 20.0 g of butyl acetate. With nitrogenblanketing, via the dropping funnel, a mixture of 26.4 g ofbis[3-trimethoxysilylpropyl]amine (Dynasylan® 1124, EVONIK, Rheinfelden)and 2.0 g of N-[3-(trimethoxysilyl)propyl]butylamine (Dynasylan® 1189,EVONIK, Rheinfelden) is added slowly dropwise. The reaction isexothermic. The rate of addition is selected such that the internaltemperature does not exceed a maximum level of 60° C. Thereafter, usingthe dropping funnel, a further 4 g of butyl acetate area added. Thereaction mixture is held at 60° C. for four hours more until titrimetricdetermination of the isocyanate content (according to DIN EN ISO 11909)gives a constant value of 8.3-8.8% NCO, based on solids).

Preparation of the Catalyst (D)

A 100 ml three-neck flask equipped with reflux condenser and stirrer ischarged under nitrogen blanketing with 11.78 g of DABCO(diazabicyclo[2.2.2]octane), 75.67 g of propanol, and 56.38 g ofisobutanol. At about 45° C., 32.24 g of bis(2-ethylhexyl) phosphate areadded slowly dropwise, during which the temperature is held at a maximumof 50° C. The mixture is stirred at 40° C. for 3 hours more. This givesa 25% strength solution of the catalyst (D).

Formulation of the Coating Materials of Inventive Examples 1 and 2 andof the Coating Materials of Comparative Examples V1 to V5 and Also ofthe Corresponding Coatings of Examples 1 and 2 and of ComparativeExamples V1 to V5

To prepare the base varnishes (S1) and (S2) of the inventive examplesand the base varnishes (VS1) to (VS5) of the comparative examples V1 toV5, the constituents indicated in table 1 are weighed out in the orderindicated (beginning from the top) into a suitable vessel in that orderand are stirred intimately with one another.

To prepare the coating materials (K1) and (K2) of inventive examples 1and 2 and also the coating materials (VK1) to (VK5) of the comparativeexamples, the stated amounts of curing agent solution (B1) are added tothe amount of base varnish indicated in table 1, in a suitable vessel,and these components are stirred intimately with one another.

TABLE 1 composition of base varnishes S1 and S2 and also VS1 to VS5 andalso of coating materials K1 and K2 and VK1 to VK5 in parts by weight V1V2 V3 V4 1 2 V5 Base varnish VS1 VS2 VS3 VS4 S1 S2 VS5 componentsPolyacrylate 49.7 49.7 49.7 49.7 49.7 49.7 49.7 polyol (A1) Tinuvin ®292¹⁾ 1.0 1.0 1.0 1.0 1.0 1.0 1.0 Tinuvin ® 384²⁾ 1.1 1.1 1.1 1.1 1.11.1 1.1 Butyl acetate 44.7 44.7 44.7 44.7 44.7 44.7 44.7 Catalyst (D)2.3 2.3 2.3 2.3 2.3 2.3 Reaction 1.0 1.0 accelerator (R)³⁾ Coscat 83⁴⁾0.1 0.1 0.1 K-Kat XK-634⁵⁾ 0.08 Benzoic acid 0.38 0.38 0.5 Sum of base98.8 98.9 99.8 99.18 99.9 99.28 97.08 varnish components Curing agent 5050 50 50 50 50 50 solution B Key to table 1: ¹⁾Tinuvin ® 292 =commercial light stabilizer from BASF SE, based on HALS ²⁾Tinuvin ® 384= commercial light stabilizer from BASF SE, based on a UV absorber³⁾Baysolvex D2EHPA = commercial bis(2-ethylhexyl) phosphate from Lanxess⁴⁾Coscat ® 83 = commercial catalyst from C. H. Erbsloh GmbH & Co. KG,based on bismuth trisneodecanoate ⁵⁾K-Kat XK-634 = catalyst from KingIndustries, based on zinc carboxylate reactive with tetramethylguanidineProduction of the Coatings of Examples 1 and 2 and of ComparativeExample V1 to V5

Bonder panels coated with commercial, cured electrocoat are coated withcommercial waterborne basecoat material (ColorBrite® from BASF CoatingsGmbH) in black or, for the testing of the thermal yellowing, in white,and are each flashed at ambient temperature for 10 minutes and thendried at 80° C. for 10 minutes. The coating materials of examples 1 and2 and of comparative examples V1 to V5 are subsequently applied, using agravity-feed cup gun, and are baked together with the basecoat at 80° C.for 30 minutes. The film thickness of the clearcoat is 30 to 35 μm, thatof the basecoat ˜15 μm.

For the testing of the NCO conversion, the completed paint was applieddirectly to Stamylan panels without basecoat, so as to produce freefilms as needed for the measurements.

Determination of the Isocyanate Conversion

The NCO conversion is determined by subjecting the samples from table 1to measurement by ATR-IR spectroscopy. For this purpose, the mixed wetspecimens of the fresh components (i.e., base varnish plus curing agent)and the applied samples as well were each spectroscoped one and 24 hoursafter oven.

For calculation of conversion, the intensity of the isocyanate band at2260 cm⁻¹ was employed, and its decrease in relation to the band of thefresh wet specimen was calculated. The spectra were standardized to theisocyanurate band at 1690 cm⁻¹, whose intensity is hardly influenced bythe crosslinking reaction. The conversion figures are compiled in table2.

Testing of the Thermal Yellowing

The coated panels on white basecoat, about 30 minutes after baking inthe forced air oven, are subjected to measurement using the X-ritemulti-angle spectrophotometer as hue measuring instrument, and adetermination is made of the b* value in the L*a*b* color space (CIELABsystem). The panels are then stored in a forced oven at 100° C. for 7days. About 1 hour after the end of storage, the panels are againsubjected to colorimetry, and the db value is determined. These resultsare found in table 2.

Testing of Micropenetration Hardness

The effect of the catalysts on the hardness of the clearcoat film wasinvestigated by means of micropenetration hardness measurements (DIN ENISO 14577-4 DE). The results are set out in table 2.

DMA Investigations, Film Properties

The storage moduli E′(200) and E′(min) and also the values for E″(max)and tan δ (max), which reflect a value for the glass transitiontemperature Tg, of the respective cured coating are measured by dynamicmechanical thermal analysis (DMTA) at a heating rate of 2 K/min with theDMTA V instrument from Rheometrics Scientific, with a frequency of 1 Hzand an amplitude of 0.2%. The DMTA measurements are carried out on freefilms having a layer thickness of 40 μm+/−10 μm. For this purpose, thecoating material under test is applied to substrates (Stamylan panels).The resulting coating is cured at a panel temperature of 80° C. for 30minutes and, after curing, is stored at 25° C. for 1 hour or 3 days,after which the DMTA measurements are carried out. The valuesascertained from these measurements are set out in table 2.

DMA Investigations, Onset/Offset

The crosslinking onset temperature of the liquid coating materials isdetermined in the context of the invention experimentally by means ofdynamic mechanical thermal analysis (DMTA). This method is described forexample in DIN EN ISO 6721-1, the method in that standard beingelucidated in the context of the determination of dynamic-mechanicalproperties of plastics. DMA uses an oscillating force applied to thesample for frequency-dependent and temperature-dependent capture of theviscoelastic properties (that is, the stiffness, expressed by themeasured storage modulus E′, and the dissipated work per vibration,expressed by the measured loss modulus (E″) of the sample. The stifferthe material, the greater the amount of the storage modulus, meaningthat the material presents a greater resistance to its elasticdeformation. For the purposes of the present invention, DMA is used todetermine the storage modulus by exposing the sample to a sinusoidualvibration of constant amplitude and frequency while continuously raisingthe temperature. For the purposes of the present invention, thetemperature at which the storage modulus begins to rise is referred toas the crosslinking onset temperature of the samples. The measurementswere carried out using a Triton 2000B instrument from Triton Technology.1 g of each of examples VB1-VB4 and B1 and B2 for measurement is appliedto a glass fiber mesh which is clamped into the instrument, and thestorage modulus E′ is measured with sinusoidual sample loading (constantfrequency, constant amplitude in the linear measurement range) for acontinuous temperature increase of 2° C. per minute. Measurement takesplace in a temperature range which is relevant for the sample (here:from 2° C. to 200° C.). The crosslinking onset temperature is thendetermined graphically from the storage modulus/temperature diagram, andis the temperature of the point of intersection of the extrapolatedbaseline of the storage modulus before the onset of crosslinking, andthe extrapolated straight line arising from the quasi-linear ascentrange of the storage modulus after the onset of crosslinking. In thisway, the crosslinking onset temperature can be determined to a precisionof +/−2° C.

Measurement of the Chemical Resistance

The chemical resistance of the coating samples was carried out 7 daysafter baking of the coating materials. The tests took place understandard conditions in accordance with DIN EN ISO 3270.

A metal test plate with dimensions of 100 mm×570 mm is used. Dependingon the test medium, 45 or 23 drops in the longitudinal direction, i.e.,1 drop per heating segment, are applied to the metal test panel prior totemperature exposure, within a maximum of 10 minutes, using an automaticpipetting system or by hand using a micropipette. The tests take placein a gradient oven at a linear temperature gradient of 35° C. to 78° C.with tolerance of ±1° C. per heating segment. The test duration in thegradient oven is 30 minutes. After the test has been carried out, themetal sample panel is washed off first with lukewarm water andsubsequently with DI water, and then cleaned using isohexane and amicrofiber cloth. As test media are used the following two chemicals:

Test Heating Chemical Concentration quantity segments Hydrochloricc(HCl) = 10.0% 25 μl 1 segment acid p.A. Sodium c(NaOH) = 5.0% 25 μl 1segment hydroxide solution p.A.

Table 2 lists the temperatures from which a change became apparent inthe coating surface.

Determination of the Scratch Resistance

The scratch resistance of the surfaces of the resulting coatings wascarried out using the Hammer test (50 back-and-forth strokes with steelwool (RAKSO®00 (fine)) and an applied weight of 1 kg, using a hammer.Subsequently the residue gloss at 20° is determined with a commercialgloss instrument. Results of the testing are found in table 2.

Measurement of Köig Pendulum Hardness

The König pendulum hardness is determined in analogy to DIN En ISO 1522DE, the results being found in table 2.

TABLE 2 test results of the coatings of examples 1 and 2 and ofcomparative examples V1 to V5 V1 V2 V3 V4 1 2 V5 NCO 23 67 14 25 43 74conversion/ % after 1 h NCO 48 77 40 52 60 85 conversion/ % after 24 hMicro- 3.12 4.58 6.57 3.62 14.21 7.13 penetration hardness 25.6 mN[N/mm²] 0.25 h Micro- 7.1 9.1 31.5 11.08 31.1 14.38 penetration hardness25.6 mN [N/mm²] 1 d Micro- 14.15 12.34 50.64 27.71 33.5 22.49penetration hardness 25.6 mN [N/mm²] 3 d Average 17.19 14.26 11.95 15.998.17 11.49 penetration depth/μm 0.25 h Average 11.49 10.21 5.53 9.275.56 8.18 penetration depth/μm 1 d Average 8.19 8.85 4.36 6.73 5.35 6.61penetration depth/μm 3 d König 10 19 19 11 29 22 pendulum hardness/number of strokes 0.25 h König 10 19 20 12 29 22 pendulum hardness/number of strokes 1 h König 10 19 20 12 29 22 pendulum hardness/ numberof strokes 2 h König 12 21 22 14 29 24 pendulum hardness/ number ofstrokes 6 h König 19 25 34 24 35 30 pendulum hardness/ number of strokes1 d Gradient <36° C.   53° C. 39° C. 53° C. 56° C. 50° C. ovenhydrochloric acid Gradient <36° C.   <36° C.   <36° C.   <36° C.   40°C. 40° C. oven sodium hydroxide solution Thermal 0.43 0.49 0.46 0.450.49 0.49 0.84 yellowing db value E″max 1 h 13° C. 30° C. 17° C. 22° C.35° C. 39° C. E″max 3 d 44° C. 44° C. 52° C. 50° C. 60° C. 48° C. tanδmax 35° C. 46° C. 43° C. 44° C. 51° C. 54° C. 1 h tanδ max 58° C. 57° C.66° C. 63° C. 74° C. 59° C. 3 d E′min 1 h/ 1.7 1.7 2.9 2.4 3.2 2.8 10⁷Pa E′min 3 d/ 2.8 2.1 4.0 3.5 4.9 2.9 10⁷ Pa E′200° C./E′ 4.2 3.3 2.43.1 1.6 2.2 min 1 h E′200° C./E′ 2.4 2.4 1.5 1.9 1.4 2.0 min 3 d Onset63 46 53 59 43 43 temperature/ ° C. Offset 22 21 16 19 14 14 time/minHammer 44 60 92 60 84 54 test 50 back- and-forth strokes/ residual gloss%Discussion of the Test Results:

The comparison of comparative example V1 (only DABCO-blocked phosphoricacid partial ester (D)) with comparative example V2 (DABCO-blockedphosphoric acid partial ester (D) plus bismuth carboxylate (Z)) shows,as does the comparison of example 1 (combination of DABCO-blockphosphoric acid partial ester (D), bismuth carboxylate (Z), andphosphoric acid partial ester (R)) both with comparative example V1(only DABCO-blocked phosphoric acid partial ester (D)) and withcomparative example V3 (DABCO-blocked phosphoric acid partial ester (D)plus phosphoric acid partial ester (R)), that the addition of thebismuth carboxylate (Z) significantly increases the isocyanateconversion, with the increase in the isocyanate conversion coming outsubstantially higher through the addition of the bismuth carboxylate (Z)in comparative example V2 without the addition of the reactionaccelerator (R) based on phosphoric acid partial ester, than forsimultaneous addition of the bismuth carboxylate (Z) and of the reactionaccelerator (R) based on phosphoric acid partial ester, as in inventiveexample 1.

In spite of this lower isocyanate conversion in inventive example 1 incomparison to the isocyanate conversion of comparative example V2,however, the inventive coating of example 1, relative not only tocomparative example V1 but also to comparative example V2 and tocomparative example V3, exhibits a very significantly improvedmicropenetration hardness, a very significantly improved averagepenetration depth, and a significantly improved resistance toward sodiumhydroxide solution. The addition of the reaction accelerator (R)produces a significantly improved silane crosslinking, as shown by thecomparison of comparative examples V1 and V2 with inventive example 1.

Furthermore, the comparison of example 1 (combination of DABCO-blockedphosphoric acid partial ester (D), bismuth carboxylate (Z), andphosphoric acid partial ester (R)) with comparative example V1 (onlyDABCO-blocked phosphoric acid partial ester (D)) and with comparativeexample V2 (DABCO-blocked phosphoric acid partial ester (D) plus bismuthcarboxylate (Z)) shows that through the addition of bismuth carboxylate(Z), additionally, the start of crosslinking (that is, the onsettemperature) begins at significantly lower temperatures of 46° C. incomparative example V2 and of only in fact 43° C. in inventive examples1 and 2 than without the addition of the bismuth carboxylate (Z) incomparative example V1 with an onset temperature of 66° C. and incomparative example V3 (DABCO-blocked phosphoric acid partial ester (D)and phosphoric acid partial ester (R)) with onset temperature of 63° C.

While in comparative example V3, as a result of the addition of thereaction accelerator (R), there is a slight reduction likewise in theonset temperature, with a value of 53° C., in comparison to comparativeexample V1, with a value of 63° C., the onset temperature isnevertheless significantly higher than in inventive examples 1 and 2,with an onset temperature of only 43° C. At the same time, however, theOH/NCO conversion in comparative example V3 is by far the lowest, and isindeed lowered even further in comparison with comparative example V1.This means that in comparative example V3, the addition of the reactionaccelerator (R) actually inhibits the OH/NCO reaction.

Moreover, the pendulum hardness, measured in each case after 0.25 h, 1h, 2 h, and after 6 h, of the resulting coatings of the inventiveexamples 1 and 2 is substantially higher than that of the resultingcoatings of all comparative examples V1 to V4.

Lastly, surprisingly, the chemical resistance with respect to sodiumhydroxide solution of the resulting coatings of inventive examples 1 and2 is higher than that of the resulting coatings of all comparativeexamples V1 to V4, and the chemical resistance toward hydrochloric acidof the resulting coatings of inventive examples 1 and 2 is higher thanthat of the resulting coatings of comparative examples V1 and V3. Hencethe more the reaction accelerator (R) improves the silane crosslinking,the more the OH/NCO reaction is inhibited at the same time. This makesit clear that the various catalysts (D) and (Z) and also the reactionaccelerator (R) all influence one another and that only in accordancewith the invention has a balanced mixture been found that results bothin very good silane crosslinking and in very good OH/NCO conversion andhence ensures the outstanding level of properties of the inventivecoating even when the coating is cured at moderate temperatures of notmore than 90° C.

No further investigation was carried out of the resulting coating ofcomparative example 5, since the thermal yellowing was at anunacceptably high level.

What is claimed is:
 1. A coating material composition, comprising: (A)at least one polyhydroxyl group-containing component (A); (B) at leastone component (B) having on average at least one isocyanate group andhaving on average at least one of at least one hydrolyzable silane groupof the formula (I):—NR—(X—SiR″_(x)(OR′)_(3-x))  (I), and at least one hydrolyzable silanegroup of the formula (II):—N(X—SiR″_(x)(OR′)_(3-x))_(n)(X′—SiR″_(y)(OR′)_(3-y))_(m)  (II), (D) atleast one phosphorus and nitrogen-containing catalyst (D) forcrosslinking of silane groups; and (Z) at least one catalyst (Z) forreaction of hydroxyl groups with isocyanate groups, wherein: Rrepresents hydrogen, alkyl, cycloalkyl, aryl, or aralkyl, it beingpossible for the carbon chain to be interrupted by nonadjacent oxygen,sulfur, or NRa groups, where Ra=alkyl, cycloalkyl, aryl, or aralkyl; R′represents hydrogen, alkyl, or cycloalkyl, it being possible for thecarbon chain to be interrupted by nonadjacent oxygen, sulfur, or NRbgroups with Rb=alkyl, cycloalkyl, aryl, or aralkyl; X, X′ independentlyrepresent linear and/or branched alkylene or cycloalkylene radicalhaving 1 to 20 carbon atoms; R″ represents alkyl, cycloalkyl, aryl, oraralkyl, it being possible for the carbon chain to be interrupted bynonadjacent oxygen, sulfur, or NRc groups, with NRc=alkyl, cycloalkyl,aryl, or aralkyl; n represents 0 to 2; m represents 0 to 2; m+nrepresents 2; x, y represents 0 to 2; the catalyst (Z) is selected fromthe group consisting of: zinc carboxylates, bismuth carboxylates, andmixtures thereof, aluminum chelates, zirconium chelates, titaniumchelates, boron chelates, and mixtures thereof, inorganic,tin-containing catalysts, and mixtures thereof; and the coating materialcomposition comprises at least one reaction accelerator (R) which isselected from the group consisting of inorganic acids, organic acids,partial esters of the inorganic acids, partial esters of the organicacids, and mixtures thereof.
 2. The coating material composition asclaimed in claim 1, comprising at least one component (B) having onaverage at least one hydrolyzable silane group of the formula (I) and atleast one hydroylzable silane group of the formula (II).
 3. The coatingmaterial composition as claimed in claim 1, wherein the phosphorus- andnitrogen-containing catalyst (D) is selected from the group consistingof amine adducts of optionally substituted acyclic phosphoricmonoesters, amine adducts of optionally substituted cyclic phosphoricmonoesters, amine adducts of optionally substituted acyclic phosphoricdiesters, amine adducts of optionally substituted cyclic phosphoricciesters, amine adducts of acyclic phosphonic diesters, amine adducts ofcyclic phosphoric diesters, amine adducts of acyclic diphosphonicdiesters, amine adducts of cyclic phosphonic diesters, and mixturesthereof.
 4. The coating material composition as claimed in claim 1,wherein the catalyst (Z) is selected from the group consisting of zinccarboxylates and bismuth carboxylates.
 5. The coating materialcomposition as claimed in claim 1, wherein the reaction accelerator (R)is selected from the group consisting of alkylphosphonic acids,dialkylphosphinic acids, phosphonic acid, diphosphonic acid, phosphinicacid, optionally substituted acyclic phosphonic monoesters, optionallysubstituted cyclic phosphoric monoesters, optionally substituted acyclicphosphoric diesters, optionally substituted cyclic phosphoric diesters,and mixtures thereof.
 6. The coating material composition as claimed inclaim 1, wherein the reaction accelerator (R) is selected from the groupconsisting of optionally substituted acyclic phosphoric monoesters,optionally substituted cyclic phosphoric monoesters, optionallysubstituted acyclic phosphoric diesters, optionally substituted cyclicphosphoric diesters, and mixtures thereof.
 7. The coating materialcomposition as claimed in claim 1, wherein: the phosphorus- andnitrogen-containing catalyst (D) is at least one adduct ofdiazabicyclo[2.2.2]octane, dimethyldodecylamine, triethylamine, or amixture thereof, with acyclic phosphoric monoesters, cyclic phosphoricmonoesters, acyclic phosphoric diesters, cyclic phosphoric diesters, ora mixture thereof; the catalyst (Z) is a Bi(III) salts of at least onebranched C3 to C24 fatty acid; and the reaction accelerator (R) is anacyclic phosphoric diester, a cyclic phosphoric diester, or a mixturesthereof.
 8. The coating material composition as claimed in claim 1,wherein a total amount of the catalyst (D) plus the catalyst (Z) plusthe accelerator (R) ranges from 0.2 to 21 wt %, based on the bindercontent of the coating material composition.
 9. The coating materialcomposition as claimed in claim 1, comprising: the catalyst (D) infractions of 0.1 to 15 wt %; the catalyst (Z) in fractions of 0.005 to1.0 wt %; and optionally the reaction accelerator (R) in fractions of0.05 to 10.0 wt %, based in each case on the binder content of thecoating material composition.
 10. The coating material composition asclaimed in claim 1, wherein 5 to 75 mol of isocyanate groups originallypresent in the component (B) have undergone conversion to silane groupsof the formula (I), the formula (II), or both.
 11. The coating materialcomposition as claimed in claim 1, wherein 5 to 55 mol % of isocyanategroups originally present in the component (B) have undergone conversionto silane groups of the formula (II).
 12. The coating materialcomposition as claimed in claim 1, comprising: from 20.0 to 80.0 wt %,of the at least one hydroxyl-containing polyacrylate (A); and from 20.0to 80.0 wt of the component (B), based on the binder content of thecoating material composition.
 13. A multistage coating process,comprising applying a pigmented basecoat to an optionally precoatedsubstrate and thereafter applying a coat of the coating materialcomposition of claim
 1. 14. The multistage coating process as claimed inclaim 13, wherein following application of the pigmented basecoat, theapplied basecoat material is first dried at temperatures from roomtemperature to 80° C. and, following the application of the coatingmaterial composition, it is cured at temperatures between 20 and 100° C.15. A clearcoat material, comprising the coating material composition ofclaim
 1. 16. A multicoat effect and/or color paint system, comprising atleast one pigmented basecoat and at least one clearcoat disposedthereon, wherein the clearcoat has been produced from a coating materialcomposition of claim 1.